Fix ack status code to be uint8

Author: addshore

src/modules/comms/comms.toit

@@ -248,7 +248,7 @@ class Comms:
       // ACK these messages...
       ack-msg := messages.ACK.msg --data=null
       ack-msg.header.data.add-data-uint32 protocol.Header.TYPE-RESPONSE-TO-MESSAGE-ID msg.msgId
-      ack-msg.header.data.add-data-uint32 protocol.Header.TYPE_MESSAGE_STATUS protocol.Header.STATUS_OK
+      ack-msg.header.data.add-data-uint8 protocol.Header.TYPE_MESSAGE_STATUS protocol.Header.STATUS_OK
       send-via-outbox ack-msg
 
     isBad := msg.header.data.has-data protocol.Header.TYPE-MESSAGE-STATUS and msg.msg-status > 0